The crashtest was failing because WebGPU is not available on the test machine - perhaps because the task requires software webrender. Regardless, we know that WebGPU adapters are available on some of our CI tasks, so the fix is to simply make this bug's crashtest cope with WebGPU being unavailable.
Bug 1809567 Comment 20 Edit History
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The crashtest was failing because WebGPU is not available on the test machine - perhaps because the task requires software webrender. There are also cases where WebGPU is disabled by blocklist entries. Regardless, we know that WebGPU adapters are available on some of our CI tasks, so the fix is to simply make this bug's crashtest cope with WebGPU being unavailable.